The present invention relates to a method for providing a design pattern on a metal stencil for screen printing which is provided with a patternable covering layer, by locally subjecting the patternable covering layer, in accordance with a predetermined pattern, to the influence of high energy radiation in beam form, as a result of which parts of the covering layer are removed.
It is known from Patent Specification No. 241567 from the German Democratic Republic to provide a pattern in a covering layer which is present on the surface of a stencil for screen printing, the pattern being formed by programmed control of a laser beam in a manner such that a pattern, permeable to a printing medium, is formed in the resist layer in accordance with a predetermined pattern.
It is possible with such a known method to provide a pattern in a resist layer which is present on a stencil for screen printing, in a reproducible manner. The method has, however, the disadvantage in that the edge sharpness of the patterns formed in this manner leaves something to be desired. It is generally noticed, specifically at the places at which the patterned resist layer spans a perforation in the stencil and where part of the resist has to be removed in the perforation, while the remaining part has to be retained, that the entire resist layer is removed from the perforation. The consequence of said complete removal is that, on printing with such stencils, a considerable degree of loss of definition is noticed at the edge of patterns as a result of a serration effect which is very disadvantageous, especially when forming patterns of very fine detail, for the end result of the printing process.